After canceling his appearance at a morning campaign rally in Orlando, Fla., President Barack Obama walks toward the White House in a driving rain after returning to Washington to monitor preparations for early response to Hurricane Sandy, Monday, Oct. 29, 2012. (AP Photo/Jacquelyn Martin)

The "October Surprise" turned out to be a monster storm that is forcing President Barack Obama and challenger Mitt Romney to overhaul campaign plans.

The political calculus for Hurricane Sandy is a delicate balancing act for both.

Obama, who returned to Washington Monday from a campaign trip to Florida, doesn't want to be seen as politicking during a crisis potentially affecting 50 million people.

Yet it's also an opportunity to appear in control and presidential. "I'm not going to be able to campaign as much over the next few days," he said.

Romney stumped in the Midwest on Monday but canceled stops in Virginia on Sunday and in New Hampshire on Tuesday. He does not have as commanding a platform as the president and was tempering criticism of the president while expressing concern for storm victims and support for relief efforts.

"Ann and I are keeping the people in Hurricane Sandy's path in our thoughts and prayers," Romney said. He urged people in a tweet to support the Red Cross.

Four critical battleground states are directly affected — North Carolina, Virginia, Ohio and New Hampshire. Consider the millions of dollars spent on political TV ads that potentially won't be seen because of power outages.

Presidents and hurricanes have had a stormy relationship.

President George W. Bush drew wide criticism for his administration's handling of Hurricane Katrina in 2005.

President Bill Clinton cut short a New Zealand trip in 1999 to deal with Hurricane Floyd.

President George H.W. Bush was blamed for a slow federal response to Hurricane Andrew in August 1992.

The previous November, Bush suffered heavy personal loss when a fierce hurricane-like nor'easter — later memorialized as "The Perfect Storm" — devastated the ground floor of his seaside home in Kennebunkport, Maine.